// Copyright 2015 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "ui/gfx/win/singleton_hwnd_observer.h"

#include "ui/gfx/win/singleton_hwnd.h"

namespace gfx {

SingletonHwndObserver::SingletonHwndObserver(const WndProc& wnd_proc)
    : wnd_proc_(wnd_proc)
{
    DCHECK(!wnd_proc.is_null());
    SingletonHwnd::GetInstance()->AddObserver(this);
}

SingletonHwndObserver::~SingletonHwndObserver()
{
    ClearWndProc();
}

void SingletonHwndObserver::ClearWndProc()
{
    if (!wnd_proc_.is_null()) {
        SingletonHwnd::GetInstance()->RemoveObserver(this);
        wnd_proc_.Reset();
    }
}

void SingletonHwndObserver::OnWndProc(HWND hwnd,
    UINT message,
    WPARAM wparam,
    LPARAM lparam)
{
    wnd_proc_.Run(hwnd, message, wparam, lparam);
}

} // namespace gfx
